Gas turbine engines are used to power aircraft, watercraft, power generators, and the like. Gas turbine engines typically include a compressor, a combustor, and a turbine. The compressor compresses air drawn into the engine and delivers high pressure air to the combustor. In the combustor, fuel is mixed with the high pressure air and is ignited. Products of the combustion reaction in the combustor are directed into the turbine where work is extracted to drive the compressor and, sometimes, an output shaft. Left-over products of the combustion are exhausted out of the turbine and may provide thrust in some applications.
Blades of the turbine capture energy from the products of the combustor as they expand causing rotation of the turbine. The interaction of combustion products with the blades heats the blades. The blades are often made from high-temperature compatible materials and are sometimes actively cooled by supplying air to the blades. To this end, some blades incorporate composite materials to withstand very high temperatures. Design and manufacture of blades from composite materials presents challenges.